Router Plane

Monday, January 7, 2019

Kitchen Spatula & Chopping Block - #6 Milling Sub-Assemblies & More Gluing


With flat surfaces I could use the table saw to square up the edges.  To do that, first the blade in the table saw needs to be changed from a rip blade to a crosscut blade.  The crosscut blade has different tooth geometry and a lot more teeth.

The short ends were in good shape but the long dimension needed a little help.   As the piece was way to long to square using the chop saw, the table saw crosscut fence or my sled I used an 8’ level clamped to the rip fence and a shim to cut one edge square to the ends.  The shim represents the amount the piece is out of square along its entire length.  To make this work the high point and the shim has to be in contact with the straight edge the entire length of the cut.  Because the rip fence is not long enough, I add the level as my true full length reference.  The same process is used to square the thin maple glued panels I did earlier.


Stacking the maple panels and the just completed cherry/maple sub-assemblies up I could get an idea of what the brick pattern really would look like. 


With the sub-assemblies all nice flat and square I can cut them up.  Each of the 5 panels are cut into 5 pieces a little over 2” wide.  This will give me my finished chopping block thickness of nearly 2”.  I decided leave the 8’ level on as an extra-long straight edge.  With everything set I made the cuts and stacked them up until I got ready to start the final assembly process

Now it’s time to cut the maple panels into strips about 2” wide to match the rough thickness of the chopping block.  Because the panels are pretty thin and the grain runs 90 degrees to what you would think they are pretty flimsy so I have to handle them carefully.  I needed to change the temporary fence on the table saw because there is a small gap under both it and the table saw rip fence.  A different temporary fence is needed as I don’t want to run the risk of the thin panel slipping under the fence and messing up my cut.  Last, I set the cut width and start running the panels through making a stack of bed joint parts.  Once cut the pieces don’t have a lot of strength and need to be supported in a couple of places as they could easily snap in half.  Here you can see what I mean about the grain direction in a finished part.

Final assembly of all the pieces can now start.  Here is what the first section looks like in a test clamp.  I decided to do the assembly in stages to keep the number of pieces I had to work with down.

The photo below shows how I have things set up with the one block done and the next series of pieces ready to be added.    On the left are the 2” wide cherry/maple strips and on the right are the thin maple pieces both ready to have the glue applied.  The center is where I will do the assembly and clamping.  The actual process is the same as the initial glue-up of the sub-assemblies.








Ever wonder how I get the photos?  Well here is the setup for the previous image.  To get the right perspective I needed to get far enough back and high enough for the image to make sense.  The solution was to stand the camera and tripod on the workbench.  I need to use a tripod as the exposures are fairly long in order to give me a good depth-of-field, but that’s a whole different topic.

Anyway, to keep the thin pieces corralled while applying glue I needed to clamp them in place.  However, since they are only 1/8” thick using traditional clamps would not work out to well so I used the setup below.  The strips are set on the same piece of plastic wrapped plywood use earlier to glue them up on then held in place with some thin cutoffs that use tapered wedges the apply pressure.

Back to glue-up in progress.  Here is the glued part which represents half of the chopping block cleaned up and clamped waiting to cure overnight.  

The next day I took off the clamps and then did the same two stage glue-up over two days to get the second half done and ready for the next step.  Since both of the halves get glued together, they need to be smooth and the same thickness so its back to the thickness sander to take out any irregularities and get me close to a finished surface.  I start with 36 grit in the sander.  That may seem a little extreme but this is end grain cherry and hard maple which is a pretty tough combination.  Once both pieces are flattened and to the same thickness, I move on to finer sanding grits ending with 150.

This is the last glue-up, only three pieces.  The two halves and the last thin maple strip between them.  Fewer pieces but the joint alignment is more critical.  Before if things were not quite perfect, I could run them through the thickness sander to flatten and true up.  Not this time as the piece is too big to fit through the sander so if I am off, I will need to hand sand the entire high side down to match then flip it over and do it again.  Pretty darn good incentive to get it right in the first place.


Next up – Final Glue-up, a Defect & Finishing


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